What is the first step in the DNS lookup process? The initial step in the DNS lookup process involves the client-side lookup in the local DNS cache.
When a user enters a URL into their browser, the system first checks its local DNS cache, which stores information from previous lookups.
If the requested URL is not found in the local cache, the system proceeds to the next step, which involves querying a DNS server.
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What is DNS and how it works?
DNS, also known as the Domain Name System, is a protocol that is part of the set of standards for how computers exchange data on the internet and private networks, such as the TCP/IP protocol suite.
Its primary function is to convert user-friendly domain names like “google.com” into Internet Protocol (IP) addresses like 172.217.0.4, which computers use to identify each other on the network.
It can be thought of as your computer’s internet GPS. Without DNS, it would be extremely challenging to remember the IP addresses of every website we want to visit.
DNS Process Steps
The DNS process involves multiple steps. Initially, the client checks its local DNS cache.
If the cache does not contain the required information, the system sends a DNS query to the recursive DNS servers of your Internet Service Provider (ISP).
If the recursive server does not have the information, it then queries the root DNS servers. Although the root servers do not possess the IP address of the domain, they can direct the query to the Top-Level Domain (TLD) servers.
The TLD servers then guide the query to the authoritative DNS servers for the specific domain. The authoritative server provides the IP address for the domain, which is then returned to the client.
The client can then establish a connection with the server at that IP address.
Where are the DNS address resolutions stored
DNS address resolutions are primarily stored in DNS cache. This cache can be found in various locations, such as a user’s computer operating system, web browsers, recursive DNS servers, and routers.
The cache retains the IP addresses of websites that a user’s computer has previously accessed.
If a website’s IP address is present in the cache, the DNS lookup process concludes there and the website is loaded. If not, the DNS lookup process continues to the ISP’s recursive DNS servers.
DNS Example
Let’s consider an example. Imagine you wish to visit “www.example.com”. Initially, your computer will check its local DNS cache.
If it doesn’t find the IP address for “www.example.com”, it will send a query to your ISP’s recursive DNS servers.
These servers will then communicate with root servers, TLD servers, and ultimately the authoritative DNS servers for “example.com” to discover the corresponding IP address.
Once the IP address is obtained, it is returned to your computer, allowing the website to be loaded.
DNS Protocol
The DNS protocol is a set of rules that govern how computers should communicate during a DNS lookup. It operates using TCP and UDP port 53.
The protocol defines the structure of DNS messages and outlines the process of converting domain names into IP addresses.
It involves a series of steps that entail querying different DNS servers and interpreting the responses until the correct IP address is found.
Where are DNS records stored in Windows 10
DNS records in Windows 10 are stored in the DNS cache, which serves as a temporary database in your computer’s memory.
This cache holds information about recent visits and attempted visits to websites and other internet domains.
To view the DNS cache entries, you can access the Command Prompt and enter the command “ipconfig /displaydns”. If you need to clear the cache, you can use the command “ipconfig /flushdns”.
Conclusion
To summarize, the DNS system plays a vital role in the internet by translating user-friendly domain names into IP addresses.
This process involves multiple steps, starting from the local DNS cache and potentially involving various DNS servers. The DNS protocol establishes the guidelines for this process.
Having a good understanding of how DNS works and where DNS records are stored can assist in troubleshooting internet connection issues and optimizing network performance.